Not applicable

Oct 18, 2013
06:30 AM

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Oct 18, 2013
06:30 AM

Does anybody have some floating point performance measurements at hand? I have testet a loop with a single instruction and got these results:

Instruction / MFLOPS:

a = b * c:

a += b * c:

a = b + c:

a += b + c:

a = b / c:

a += b / c:

The variables a,b,c are floats (32bit). I compiled the test program without optimizations (-O0).

Are these values reasonable?

Best regards, Uli

Instruction / MFLOPS:

a = b * c:

7,5

a += b * c:

6,3

a = b + c:

7,5

a += b + c:

6,3

a = b / c:

4,1

a += b / c:

3,7

The variables a,b,c are floats (32bit). I compiled the test program without optimizations (-O0).

Are these values reasonable?

Best regards, Uli

- Tags:
- IFX
- xmc4500 fpu flops

5 Replies

Oct 20, 2013
11:40 PM

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Oct 20, 2013
11:40 PM

Uli wrote:

Does anybody have some floating point performance measurements at hand? I have testet a loop with a single instruction and got these results:

Instruction / MFLOPS:

a = b * c:7,5

a += b * c:6,3

a = b + c:7,5

a += b + c:6,3

a = b / c:4,1

a += b / c:3,7

The variables a,b,c are floats (32bit). I compiled the test program without optimizations (-O0).

Are these values reasonable?

Best regards, Uli

This is pretty subjective as calculation equation is different for different user. However it would be good to pull an IO high before calculation and pull the IO Low after the calculation to understand the duration of the calculation.

Not applicable

Oct 21, 2013
02:10 AM

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Oct 21, 2013
02:10 AM

Oct 21, 2013
07:30 PM

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Oct 21, 2013
07:30 PM

Uli wrote:

Thanks for your input. Why would this type of calculation be subjective? I can't think of any reasons except compiler options. Or do you have concerns that the method of timing these operations is not reliable?

I guess you are doing some kinds of performance evaluation with the above mentioned calculations. What I mean is that some customer has other method of performance evaluation (eg. Doing square root etc) to suit their needs, therefore it is subjective.

Not applicable

Oct 21, 2013
10:49 PM

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Oct 21, 2013
10:49 PM

Not applicable

Oct 23, 2013
07:24 AM

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Oct 23, 2013
07:24 AM

Doesn't Infineon provide some kind of DSP performance benchmark for the XMC4000 series?